Effect of proximity of buloke (Allocasuarina luehmannii) trees on buloke early sapling survival in a semiarid environment

2013 ◽  
Vol 61 (4) ◽  
pp. 302 ◽  
Author(s):  
John W. Morgan ◽  
Paulius A. Kviecinskas ◽  
Martine Maron

Agricultural intensification has led to the dramatic decline of buloke (Allocasuarina luehmannii) and the plant communities it dominates in southern Australia. Conservation of remnant buloke woodlands and revegetation of agricultural land are both required for the persistence and improved ecological function of this threatened community. We examined the effect of proximity of mature buloke trees on early sapling survival, to provide guidelines for revegetation aimed at enhancing degraded remnants. We planted buloke saplings at different distances from the base of remnant mature trees at a site in western Wimmera, Victoria, with and without herbaceous competition. Mature buloke trees altered most soil nutrients (positively), soil water content (negatively) and soil conductivity (positively) at different gradients from the tree base, depending on the factor measured. Mature buloke trees had a strong negative effect on conspecific sapling survival in the first summer after planting in both the presence and absence of an herbaceous understorey, possibly because of the strong effect of trees on soil moisture. Competition from mature buloke was high nearest to the trees (up to 9 m from tree base), but competition from the native understorey also appeared important for saplings in the tree gaps, as evidenced by their improved survival when the understorey was removed. We suggest that to establish buloke saplings in areas where mature trees already occur (i.e. enhancement plantings around isolated paddock trees), planting tubestock outside the canopy of mature buloke is necessary to enhance establishment success.

Land ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 64
Author(s):  
Żanna Stręk ◽  
Przemysław Leń ◽  
Justyna Wójcik-Leń ◽  
Paweł Postek ◽  
Monika Mika ◽  
...  

In many countries of the world, rural areas are characterized by a defective spatial structure of agricultural land. The most frequent defects are large fragmentation and distribution of farmland. The fragmentation of land has been an issue widely described by many authors throughout the world. The problem of the distribution of land owned by individual farmers is slightly different, since due to the complexity of the problem this issue was not widely explored in Poland (plot patchwork) or in other countries of Europe and the world. Land fragmentation and distribution of plots in rural areas has a negative effect on the profitability and efficiency of agricultural production. Land consolidation and exchange is an operation facilitating spatial structure improvement. The authors attempted to develop a universal land exchange algorithm for eliminating the external plot patchwork. As it turns out, so far no land exchange algorithm has been developed. Specific analyses were carried out in Puchaczów commune, county of Łęczna, Lublin voivodeship in the eastern part of Poland, covering an area of 6907.80 ha, split into 15,211 plots. The chequerboard arrays method was used. The publication presents the algorithm and its practical application using a test sample. A result of the studies is a proposal concerning the exchange of land between landowners in the villages of the commune of Puchaczów. Using the algorithm, the area of individual lands in the commune, after the exchange, will increase by 172.09 ha, which is 2.5% for the area of individual lands, and 1.9% for the commune.


2012 ◽  
Vol 18 (4) ◽  
pp. 263 ◽  
Author(s):  
Tom Lewis ◽  
David Taylor ◽  
Scott Swift ◽  
Valerie Debuse

We monitored an area that was revegetated with the goal of restoring a Eucalyptus tereticornis open forest on former agricultural land in central, eastern Queensland. Revegetation involved: (1) planting 60 ha of previously cleared and heavily grazed land with eight local trees species; and (2) removing cattle grazing to encourage natural regeneration in areas where some mature trees remained. We compared the revegetation site to native pasture that had also been previously cleared, with only scattered paddock trees remaining, and continued to be managed for livestock production (an area similar to the revegetation site, prior to planting) and a remnant forest (reference area). Nine years since revegetation began there was some evidence that the revegetated site was diverging from pasture in terms of understorey plant composition, sapling density and topsoil C and N. There was little divergence in terms of plant species richness (native, introduced, grass, forb and woody plant richness), herbaceous biomass and woody plant regeneration. Some monitoring plots were subject to fire (prescribed fire and or wildfire) over the period of monitoring. With increasing time since fire, the richness of native species, introduced species and grass species (both native and introduced) declined, and forb and grass species richness declined with increasing litter biomass, suggesting that the occurrence of fire and the associated removal of litter biomass has a positive influence on herbaceous diversity in this ecosystem. Woody plant regeneration persisted through lignotubers at the revegetation site and at the pasture, but this regeneration was stunted at the pasture presumably due to livestock grazing. Hence areas of former E. tereticornis forest showed promising regenerative capacity where mature trees remained and where livestock grazing was removed.


Author(s):  
Kurniatun Hairiah

Maintaining and where feasible restoring soil carbon stocks is part of all sustainable development strategies that have a chance of meeting the global commitment of the Paris Agreement to contain global warming within a 1.5<sup>o</sup>C limit. Active policies to incentivize increased soil carbon storage require under­standing of the drivers of soil carbon decline, as well as the conditions under which soil management leads to an increase. Soil carbon transitions -- shifts from decline to increase of soil carbon stocks -- have been recorded as part of agricultural intensification. Organic inputs supporting soil carbon may primarily depend on roots, rather than aboveground inputs, and thus on the choice of crops, trees, and grasses that make up an agricultural land use system.


Author(s):  
Halima M. ◽  
Sneha Unnikrishnan ◽  
Karthikeyan Ramalingam

Across the globe, in both developed and developing countries, wheat provides the fundamental support for all other important foods. However, due to climate change, environmental stress, soil infertility, etc., the yield of wheat is affected. To overcome these issues, biofertilizers are recommended. They are eco-friendly, cost-efficient, and affordable by marginal farmers too when compared with chemical fertilizers. Biofertilizers are made up of living microorganisms that colonize the rhizosphere to promote plant yield and prevent plant disease. Pesticide degrading strains of bacteria are emerging as the best technique to overcome the negative effect of pesticides. Due to insufficient awareness among farmers, agricultural land and crops are cultivated through chemical fertilizers, which became a major threat to human health and agriculture. On the other hand, the government is implementing several measures in marketing bio-fertilizers for the betterment of agriculture and human health. In this chapter, the significance and future perspectives of biofertilizers have been covered.


2016 ◽  
Vol 46 (3) ◽  
pp. 376-386 ◽  
Author(s):  
Ilze Kokarēviča ◽  
Guntis Brūmelis ◽  
Raimonds Kasparinskis ◽  
Arta Rolava ◽  
Oļģerts Nikodemus ◽  
...  

Information on the long-term changes in plant communities that occur without human interference is limited, due to insufficient studies where vegetation can be resurveyed. In 1912, a strict nature protection reserve, with non-intervention management, was established on Moricsala Island in Latvia, located in the boreo–nemoral forest zone. Prior to establishment of the nature reserve, part of the island area was used for agriculture. The island is now covered almost entirely by forest dominated by Quercus robur L. and Tilia cordata Mill. on sandy soils. Resurvey was conducted in 2011 in 17 plots in which tree layers and the understory vegetation had been described in 1930. The plots were classified into two groups based on tree species composition in 1930 to determine changes in species composition. Differences in understory and tree canopy composition between these groups persisted over the period between the studies, in relation to soil factors and past stand history. Considerable turnover of species occurred, with a decrease of species typical of open habitats and replacement by species typical of nemoral (temperate deciduous) forest plant communities. In the past, Q. robur had likely established in open habitats created by agricultural land use or past fire but is presently not regenerating in the understory.


1987 ◽  
Vol 11 (1) ◽  
pp. 23-28 ◽  
Author(s):  
D. H. Van Lear ◽  
S. M. Jones

Abstract A site classification system based on vegetation and land type was developed for the Savannah River Plant (SRP) in the upper coastal plain of South Carolina. Different positions of the landscape support distinctive plant communities. Late successional plant communities and their immediate predecessors were identified on eight site types along a moisture gradient ranging from dry, sandy uplands to flooded bottoms. Late successional, near-stable plant communities, even in the highly disturbed forest ecosystems of the Southeast, act as integrators of environmental factors to reflectsite potential. Vegetation can supplement information on soils and topography in the delineation and classification of forest sites. Knowledge of site-vegetative relationships would be especially useful in making management decisions regarding wildlife habitat evaluation, hazard rating for insects, diseases, and fires, and estimating potential uses for recreation. Application of the system by practicing foresters is discussed. South. J. Appl. For. 11(1):23-28.


2020 ◽  
Author(s):  
Andrew Tweedie ◽  
Philip M. Haygarth ◽  
Anthony Edwards ◽  
Allan Lilly ◽  
Nikki Baggaley ◽  
...  

&lt;p&gt;The use of phosphorus (P) fertilizer has been one of the defining contributors to productive agriculture since the green revolution during the middle of the last century. However, these increased yields have come at the cost of dependency upon the declining resources of P rock reserves and eutrophication of water bodies downstream. In this context, it is important to understand the long-term effects of these P fertilizer additions on soil chemistry over ~50 years in order explain past and current patterns in fertilizer usage and so to better inform future soil management.&lt;/p&gt;&lt;p&gt;We tested the hypothesis that phosphorus forms and availability in mixed use (arable and grazed) agricultural soil have changed over a period of 50 to 80 years of agricultural intensification. Spatially matched samples of soil from 34 agricultural sites in North East (NE) Scotland were collected at two timepoints. The first samples were taken between 1951 and 1981 and in all cases the resampling took place in the autumn of 2017. The soils sampled were representative of agricultural soils in NE Scotland.&lt;/p&gt;&lt;p&gt;The hypothesis was tested by employing a range of soil tests on the &amp;#8216;old&amp;#8217; and &amp;#8216;new&amp;#8217; time points.&amp;#160; These included water extraction for inorganic and organic P, nitrate and ammonium and dissolved organic carbon, acid ammonium oxalate extraction to investigate the soil P exchange complex and NaOH-EDTA extraction as a strong alkaline extractant which preserves organic P forms. Analysis by &lt;sup&gt;31&lt;/sup&gt;P NMR was conducted on the NaOH-EDTA extracts from 5 pairs of samples, to investigate the organic P chemistry of in greater detail.&lt;/p&gt;&lt;p&gt;Phosphorus concentrations for stronger extractants (NaOH-EDTA, acid ammonium oxalate) did not increase significantly (P&lt;0.05) over time. However, water extraction results showed increases in total P (P&lt;0.01) and inorganic P but decreases in organic P. Additionally, analysis by &lt;sup&gt;31&lt;/sup&gt;P NMR detected changes between timepoints in &amp;#945;-glycero-phosphate and pyrophosphate.&lt;/p&gt;&lt;p&gt;These results indicate that differences in the various chemical forms of P present in soil between the timepoints can be detected many decades apart. This indicates changes in the functioning of the P cycle in these soils under intensive agricultural land use over time. Knowledge of the P-cycling response of soils under agricultural land-use over decades provides an opportunity to understand changes in soil nutrient concentrations, balances and availability and inform studies seeking to improve the sustainable management of soil fertility.&lt;/p&gt;


1981 ◽  
Vol 4 ◽  
pp. 105-143
Author(s):  
I. R. Lane

At present, only a small proportion of livestock in developing countries are kept on cultivated pastures (Williamson and Payne, 1978).This paper is therefore more concerned with the intensification of the pasture production and the levels of animal production which may be achieved. In general, the pastures which may be cultivated in an area and the ways open for their utilization are related to the ecology of that area (Bogdan, 1977; Skerman, 1977). The factors which determine the natural vegetation to be found on a site, and the distribution of the major plant communities in developing countries, will therefore be reviewed first. Then, certain ecological zones which show promise for the intensification of pastures will be selected and, for each, some of the possible lines of development will be discussed.


1999 ◽  
Vol 77 (1) ◽  
pp. 27-33 ◽  
Author(s):  
Lalita Acharya ◽  
M Brock Fenton

The defensive behaviour of moths around street lights was examined at a site where bats feed heavily on moths. The lights had a negative effect on moth defensive behaviour, but a combination of observational techniques (recording the outcome of naturally occurring bat-moth interactions) and experimental techniques (deafening moths by puncturing the tympanal organs) indicated that ultrasound-detecting ears still afforded the moths some protection from bat predation. On average, bats captured 69% of the moths they attacked. Moths that exhibited evasive behaviour were caught significantly less often than those that did not (52 vs. 2%). Moths whose tympanic organs had been punctured were significantly easier to catch (requiring fewer attempts) than moths with intact ears, reflecting the fact that significantly more of the eared than the deafened moths showed evasive behaviour (48 vs. 0%). Overall, the number of captures of deafened moths was higher, though not significantly, than the number of captures of eared moths.


2019 ◽  
Vol 37 (4) ◽  
pp. 501
Author(s):  
Elizabeth Solleiro-Rebolledo ◽  
Yazmín Rivera-Uria ◽  
Bruno Chávez-Vergara ◽  
Jaime Diaz-Ortega ◽  
Sergey Sedov ◽  
...  

In this work, we present the results of a soil study in the Teuhtli volcano, located to the south of the Basin of Mexico with the aim to understand the pedogenetic pathways and the evolution of the landscape dynamics. Two different types of soil prof iles were sampled: in “conserved” areas, with less anthropogenic influence and in sites with intense agriculture activities since pre-Hispanic times. The three conserved prof iles are located in different landscape positions: the Cima prof ile in the summit, the Ladera prof ile in the high slope, and the Yotecón in a lower position of the piedemont. The agriculture prof iles are La Cruz, La Era and El Llano, situated in the foothill. Properties in both kind of soils are similar, however, in agriculture sites, structure (evaluated in macro and microscale) is weaker, total organic carbon content is smaller and bulk density is higher. Both soils show two main pedogenetic processes: andosolization and carbonate formation. Despite the age of the parent material (36 000 years), the Andosol phase has not been lost. This is because of the geomorphological dynamics of the zone, in which the processes of erosion and colluviation promote soil loss, restarting the pedogenetic clock. The detection of lithological discontinuities (by the Ti/Zr ratio) documents these processes. By the other hand, the formation of pedogenic carbonates is governed by the seasonal conditions of drought. The age of these carbonates places their formation in the mid-Holocene, an epoch for which drier conditions are detected in other sites of the Basin of Mexico. The agricultural land use has also promoted morphological, chemical and physical changes in the soils. The continuous tillage of the sites has prevented the soils from developing. This could have a negative effect on the fertility of those soils currently used to sustain the peri-urban agroecosystems of Mexico City.


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